Works with 8g
Fork of MMA8452 by
MMA8452.cpp
- Committer:
- nherriot
- Date:
- 2013-10-08
- Revision:
- 1:ef026bf28798
- Parent:
- 0:bcf2aa85d7f9
- Child:
- 2:66db0f91b215
File content as of revision 1:ef026bf28798:
// Author: Nicholas Herriot /* Copyright (c) 2013 Vodafone, MIT License * * Permission is hereby granted, free of charge, to any person obtaining a copy of this software * and associated documentation files (the "Software"), to deal in the Software without restriction, * including without limitation the rights to use, copy, modify, merge, publish, distribute, * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all copies or * substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ # include "MMA8452.h" float TILT_XY[64] = {0, 2.69, 5.38, 8.08, 10.81, 13.55, 16.33, 19.16, 22.02, 24.95, 27.95, 31.04, 34.23, 37.54, 41.01, 44.68, 48.59, 52.83, 57.54, 62.95, 69.64, 79.86, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -79.86, -69.64, -62.95, -57.54, -52.83, -48.59, -44.68, -41.01, -37.54, -34.23, -31.04, -27.95, -24.95, -22.02, -19.16, -16.33, -13.55, -10.81, -8.08, -5.38, -2.69}; float TILT_Z[64] = {90.00, 87.31, 84.62, 81.92, 79.19, 76.45, 73.67, 70.84, 67.98, 65.05, 62.05, 58.96, 55.77, 52.46, 48.99, 45.32, 41.41, 37.17, 32.46, 27.05, 20.36, 10.14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10.14, -20.36, -27.05, -32.46, -37.17, -41.41, -45.32, -48.99, -52.46, -55.77, -58.96, -62.05, -65.05, -67.98, -70.84, -73.67, -76.45, -79.19, -81.92, -84.62}; // Connect module at I2C address using I2C port pins sda and scl Accelerometer_MMA8452::Accelerometer_MMA8452(PinName sda, PinName scl,int frequency) : m_i2c(sda, scl) , m_frequency(frequency) { //m_i2c.frequency(m_frequency); } // Destroys instance Accelerometer_MMA8452::~Accelerometer_MMA8452() { } // Setting the control register bit 1 to true to activate the MMA8452 int Accelerometer_MMA8452::activate() { char mcu_address = (MMA8452_ADDRESS<<1); char init[2]; init[0] = CTRL_REG_1; // control register 1 init[1] = 0x01; // set to active //while(m_i2c.write(mcu_address,init,2)); if(m_i2c.write(mcu_address,init,2) == 0) { // pc.printf("The initialisation worked"); return 0; // return 0 to indicate success } else { // pc.printf("The initialisation failed"); return 1; // crumbs it failed!!! } } // Device initialization void Accelerometer_MMA8452::init() { write_reg(INTSU_STATUS, 0x10); // automatic interrupt after every measurement write_reg(SR_STATUS, 0x00); // 120 Samples/Second write_reg(MODE_STATUS, 0x01); // Active Mode } // Get device ID int Accelerometer_MMA8452::Get_DeviceID(int *deviceID) { char mcu_address = (MMA8452_ADDRESS<<1); int z = 0; m_i2c.start(); wait( 0.1); if( m_i2c.write( mcu_address) == 0) { //printf( "GetDeviceId NAK on writing address"); return 1; } wait( 0.1); if( m_i2c.write( WHO_AM_I) == 0) { //printf( "GetDeviceId NAK on writing register address"); return 1; } wait( 0.1); m_i2c.start(); wait( 0.1); if( m_i2c.write( mcu_address | 0x01) == 0) // this is asking to read the slave address - even though it's a 'write' method!!! Crap API... { //printf( "GetDeviceId NAK on writing address"); return 1; } wait( 0.1); //deviceID = m_i2c.read(0); z = m_i2c.read(0); wait( 0.1); m_i2c.stop(); return 0; } // Reads the tilt angle void Accelerometer_MMA8452::read_Tilt(float *x, float *y, float *z) { const char Addr_X = OUT_X_MSB; char buf[3] = {0,0,0}; m_i2c.write(MMA8452_ADDRESS, &Addr_X, 1); // Pointer to the OUT_X_MSB register m_i2c.read(MMA8452_ADDRESS, buf, 3); // Read register content into buffer with 6bit // returns the x, y, z coordinates transformed into full degrees *x = TILT_XY[(int)buf[0]]; *y = TILT_XY[(int)buf[1]]; *z = TILT_Z[(int)buf[2]]; } // Reads x data int Accelerometer_MMA8452::read_x() { char mcu_address = (MMA8452_ADDRESS <<1); m_i2c.start(); // Start m_i2c.write(mcu_address); // A write to devic m_i2c.write(OUT_X_LSB); // Register to read m_i2c.start(); m_i2c.write(mcu_address); // Read from device int x = m_i2c.read(0); // Read the data m_i2c.stop(); return x; } // Reads y data int Accelerometer_MMA8452::read_y() { char mcu_address = (MMA8452_ADDRESS <<1); m_i2c.start(); // Start m_i2c.write(mcu_address); // A write to device 0x98 m_i2c.write(OUT_Y_MSB); // Register to read m_i2c.start(); m_i2c.write(mcu_address); // Read from device 0x99 int y = m_i2c.read(0); // Read the data m_i2c.stop(); return y; } // Reads z data int Accelerometer_MMA8452::read_z() { char mcu_address = (MMA8452_ADDRESS <<1); m_i2c.start(); // Start m_i2c.write(mcu_address); // A write to device 0x98 m_i2c.write(OUT_Z_MSB); // Register to read m_i2c.start(); m_i2c.write(mcu_address); // Read from device 0x99 int z = m_i2c.read(0); // Read the data m_i2c.stop(); return z; } // Reads xyz int Accelerometer_MMA8452::read_xyz(char *x, char *y, char *z) { char mcu_address = (MMA8452_ADDRESS <<1); char register_buffer[6] ={0,0,0,0,0,0}; const char Addr_X = OUT_X_MSB; m_i2c.write(mcu_address); // A write to device 0x98 m_i2c.write(MMA8452_ADDRESS, &Addr_X, 1); // Pointer to the OUT_X_MSB register if(m_i2c.write(mcu_address,&Addr_X,1) == 0) { if(m_i2c.read(mcu_address,register_buffer,6) == 0) { *x = register_buffer[1]; *y = register_buffer[3]; *z = register_buffer[5]; return 0; // yahoooooo } else { return 1; // failed oh nooo! } } else { return 1; // failed oh nooo! } } // Write register (The device must be placed in Standby Mode to change the value of the registers) void Accelerometer_MMA8452::write_reg(char addr, char data) { char cmd[2] = {0, 0}; cmd[0] = MODE_STATUS; cmd[1] = 0x00; // Standby Mode on m_i2c.write(MMA8452_ADDRESS, cmd, 2); cmd[0] = addr; cmd[1] = data; // New value of the register m_i2c.write(MMA8452_ADDRESS, cmd, 2); cmd[0] = MODE_STATUS; cmd[1] = 0x01; // Active Mode on m_i2c.write(MMA8452_ADDRESS, cmd, 2); } // Read from specified MMA7660FC register char Accelerometer_MMA8452::read_reg(char addr) { m_i2c.start(); // Start m_i2c.write(0x98); // A write to device 0x98 m_i2c.write(addr); // Register to read m_i2c.start(); m_i2c.write(0x99); // Read from device 0x99 char c = m_i2c.read(0); // Read the data m_i2c.stop(); return c; }